Today: A decade-long economic expansion lowers the United States unemployment rate to 4.1 percent.

1961: In the United States, 87.5 percent of all families are married couple families, and 10 percent are headed by females.

Today: Married couple families account for 79.2 percent of all families in the United States, and 16.5 percent of all families are headed by females.

1967: In his book The Medium Is the Message, writer Marshall McLuhan introduces the idea of the Global Village, claiming that advances in transportation and communication enable people to live as if time and space had vanished. People now communicate as if they lived in the same "village."

Today: The World Wide Web collapses time and space even further, enabling people simultaneous, ubiquitous and, for those in economically developed countries, inexpensive communication with others throughout the world.